1. Field of the Invention
The present invention relates to a reinforcement device for compression buckling strength and a method of fastening the same, which can improve compression buckling strength in a detachable manner, without power interruption of transmission lines, member disassembly or field preparation, so as to prevent an angle-type steel-frame member for a steel-frame structure or a steel power-transmission tower from undergoing compression buckling and accidental eccentricity.
2. Description of the Related Art
In general, a steel power-transmission tower has a truss structure, which is designed to connect steel-frame members triangularly and use tension and compressive force of the members to resist external force. Since the truss structure enables construction of a lightweight and rigid structure, it is believed to be effective against earthquakes. Here, an angle-type steel-frame member is employed not only as the steel-frame member for the steel power-transmission tower having the truss structure, but also as a brace for resisting lateral force in the steel-frame structure.
However, since the angle-type steel-frame members are vulnerable to compression buckling and accidental eccentricity, the angle-type steel-frame members are liable to fall in succession if an unexpected typhoon, strong wind or the like causes any one member to buckle. Thus, it is very important to manage straightness and partial distortion of the member.
Referring to FIG. 1, if a post of an angle-type steel-frame member is longer than a cross section thereof, the angle-type steel-frame member (an L-shaped steel corner post) receives a compressive load at opposite ends thereof and suddenly buckles when the load reaches a predetermined level.
For this reason, replacement of the steel-frame member with one having a large cross-sectional area or attachment of a plate thereto using a bolt has been suggested to reinforce the angle-type steel-frame member. However, for the steel power-transmission tower, these methods have problems in that many processes such as stoppage of power supply, member disassembly, preparation for reinforcement, and so on are needed. Further, conventional reinforcement operation for the angle-type steel-frame member requires various preceding operations, such as transmission line bypass, working diagram preparation, work-plan establishment, and the like, which consume considerable time and expenses.